Thermosetting resin composition

ABSTRACT

A thermosetting resin composition which is improved in impact resistance, thermal crack resistance, oxidative degradation resistance and thermal degradation resistance without impairing the heat resistance represented by HDT and which is suitable for the encapsulation of semiconductors and the like, is provided. The composition is comprised by (A) a thermosetting resin; (B) any of the following mono-olefin liquid polymers (a) to (c) : wherein (a) a mono-olefin liquid polymer having as least one epoxy group (hereinafter referred to as “epoxy group containing mono-olefin liquid polymer”), (b) a mono-olefin liquid polymer having at least one aldehyde group (hereinafter referred to as “aldehyde group containing mono-olefin liquid polymer”), and (c) a mono-olefin liquid polymer having at least one ketone group(hereinafter referred to as “ketone group containing mono-olefin liquid polymer”)(hereinafter the polymers (a) to (c) are collectively referred to as “reactive mono-olefin liquid polymer”); and (C) an organometallic compound and/or a metal ester compound. The composition can develop a sea-island phase structure composed of a continuous phase mainly made of a cured product of the thermosetting resin (containing a curing agent) and a dispersed phase which is mainly made of the thermosetting resin (containing a curing agent) and the reactive mono-olefin polymer wherein the whole periphery of each dispersed particle is covered with at least one interfacial phase.

TECHNICAL FIELD

The present invention relates to the improvement of impact resistanceproperties of a thermosetting resin composition which is used with “areactive mono-olefin liquid polymer” and an organometallic compoundand/or a metal ester compound and provides especially an epoxy resincompound which is improved in impact resistance, cracking resistance inthermal cracking test, oxidative degradation resistance and thermaldegradation resistance, and which is used for the encapsulation ofsemiconductors and the like.

BACKGROUND ART

A thermosetting resin is used in many applications independently orcombinations with other resins, and especially in many applications ofelectrical and mechanical components from the point of advantages suchthat electrical insulation properties are good, mechanical strength issufficient, thermal resistance is good, coefficient of thermal expansionis in low level and moreover the price is low and the like. On the otherhand, lowness of toughness is given as the worst disadvantage which iscommon to the thermosetting resin, and many studies have been conductedfor the improvements.

The impact resistance improvement of an epoxy resin composition which isone example of the thermosetting resins has been proposed by theintroduction of flexible component to epoxy resin. For example, it iswidely recognized that the use of rubber particle with core shellstructure (e.g. Refer to Patent Documents 1 and 2.), the introduction ofreactive liquid rubber (e.g. Refer to Patent Documents 3 to 5.), and theintroduction of reactive liquid polybutene (e.g. Refer to PatentDocument 6.) and the like are effective, but simultaneously thequestionable points are cleared up. For example, the method thatflexible epoxy resin is reacted with reactive material as described inreference Patent Documents 1 to 6 makes thermal resistance andmechanical strength and the like such as flexible strength to low level,and the method to add core shell structure rubber particle, for example,MBS powder (core shell resin particle of methyl methacrylate styrenebutadiene) and epoxy group containing composite acrylic rubber particleand rubber fine particle of crosslinking acrylic rubber fine particleand the like makes the increase of viscosity significantly and has aproblem of storage stability.

The method to add the reactive liquid rubber, for example.carboxyl-terminated modified butadiene acrylonitrile rubber (hereinafterreferred to as CTBN), has less occurrence of the above mentionedproblem.

Here, for the epoxy resin composition containing CTBN, during theprogress of curing reaction, CTBN which is compatibilized initially inepoxy resin generates phase separation from epoxy resin, and acontinuous phase which is formed by epoxy resin and a dispersed phasewhich is formed by CTBN, are formed (a sea-island structure), so thatthe impact resistance properties are improved by relying on the phasestructure characteristics. On the other hand, CTBN which does notgenerate phase separation and is taken into the continuous phase ofepoxy resin makes the degradation of thermal resistance which isrepresented by heat distortion temperature (hereinafter referred to asHDT) of epoxy resin. To be more precise, as for CTBN, the problem ispointed out that the control with respect to reactivity and affinityproperties based on the structure is not sufficient, and by a kind ofcuring agent and curing condition, the size and distribution of the CTBNdispersed phase varies so that the properties of the epoxy resincomposition turn to change significantly. Moreover, since CTBN hasunsaturated bond parts in the main chain, the essential problem has beenknown with respect to long term reliability such that oxidationdegradation and thermal degradation and the like easily occur. Also, asfor the liquid rubber modified epoxy resin (e.g. Refer to PatentDocument 7) which epoxy resin is modified by CTBN, and which is proposedrecently, these problems are not sufficiently solved.

On the other hand, the improvement studies on phenolic resin have beenconducted. For example, studies on the improvement of impact resistanceof specific phenolic resin by aromatic polyester (e.g. Refer to PatentDocument 8), and on toughening phenolic resin by specific polyethyleneterephthalate, polyurethane, methyl methacrylate based copolymer and thelike (e.g. Refer to Patent Document 9) have been conducted, but thosematerials are extremely unsatisfactory where the improvement ontoughening is insufficient and flowability deteriorates and the like.

As for phenolic resin, the improvement of impact resistance by use ofreactive liquid rubber is widely studied method. For example, thekneeding method of emulsion polymerization latex of the functionalrubber having functional groups such as epoxy group, hydroxyl group,carboxyl group, and amino group to phenolic resin(e.g. Refer to PatentDocument 10), the method that conjugated diene based rubber latex as NBRand the like which has good compatibility under making to contain theanion based surface active agent, is made to disperse into resin beforedehydration process of phenolic resin (e.g. Refer to Patent Document11), and the compounding method of epoxy polybutadiene and radicalpolymer initiator at kneeding compound materials(e.g. Refer to PatentDocument 12), are inevitable to degrade flowability significantly whenthe rubber is added to the extent that toughening of phenolic resintakes effect. Accordingly, there are problems to impair the practicalprocessability and with toughening, the excellent thermal resistance ofthe phenolic resin deteriorates.

-   [Patent Document 1] JP61-42941 B-   [Patent Document 2] JP 2-117948 A-   [Patent Document 3] JP58-25391 B-   [Patent Document 4] JP10-182937 A-   [Patent Document 5] JP3036657 B-   [Patent Document 6] EP045749A-   [Patent Document 7] JP 2001-089638 A-   [Patent Document 8] JP61-168652 A-   [Patent Document 9] JP62-209158 A-   [Patent Document 10] JP 62-59660A-   [Patent Document 11] JP3-17149 A-   [Patent Document 12] JP 3-221555A

DISCLOSURE OF INVENTION

The present invention is to provide a thermosetting resin compositionsuch as epoxy resin and phenolic resin and the like which improvesimpact resistance, thermal crack resistance, oxidative degradationresistance and thermal degradation resistance without impairing heatresistance represented by HDT and is suitable for the encapsulation ofsemiconductors and the like.

As the result of keen studies, the inventor discovered that the aboveobjective can be accomplished by use of a “reactive mono-olefin liquidpolymer” and an organo-metallic compound and/or a metal ester compoundand completed the present invention.

The first aspect of the present invention relates to a thermosettingcomposition comprising (A) a thermosetting resin, (B) any of thefollowing liquid mono-olefin polymers (a) to (c) wherein:

(a) a liquid mono-olefin polymer having as least one epoxygroup(hereinafter referred to as “epoxy group containing mono-olefinliquid polymer”), (b) a liquid mono-olefin polymer having at least onealdehyde group(hereinafter referred to as “aldehyde group containingmono-olefin liquid polymer”),

(c) a liquid mono-olefin polymer having at least one ketonegroup(hereinafter referred to as “ketone group containing liquidmono-olefin polymer”)(hereinafter the polymers (a) to (c) arecollectively referred to as “reactive mono-olefin liquid polymer”), and(C) an organometallic compound and/or a metal ester compound.

The second aspect of the present invention according to the first pointof the present invention relates to the thermosetting compositioncomprising wherein the “reactive mono-olefin liquid polymer” comprisesthe “epoxy group containing mono-olefin liquid polymer” which epoxygroup is formed on the terminal carbon as the above mentioned (a),and/or the “aldehyde group containing mono-olefin liquid polymer” whichthe aldehyde group is formed on the terminal carbon as the abovementioned (b).

The third aspect of the present invention according to any of the firstpoint and the second point of the present invention relates to thethermosetting composition comprising wherein 80% or more of repeatedunit in any main chain structure of the “reactive mono-olefin liquidpolymer” is represented by the structure of Formula (1).

The fourth aspect of the present invention according to any of the firstpoint to the third point of the present invention relates to thethermosetting composition comprising wherein the number-averagemolecular weight of any of the “reactive mono-olefin liquid polymer” isin the range of 300 to 6,000.

The fifth aspect of the present invention according to any of the firstpoint to the fourth point of the present invention relates to thethermosetting composition comprising wherein “the organometalliccompound and/or the metal ester compound” is any of (d) to (f).

(d) Kind of metal is any of cobalt, tin, zinc, copper.

(e) Organic structure part is paraffin or fatty acid having chain branchof 10 or less carbons of the main chain.

(e) Organic structure part is naphthenic acid based fatty acid.

The sixth aspect of the present invention according to any of the firstpoint to the fifth point of the present invention relates to thethermosetting composition comprising wherein the main phase structure ofthe resin phase is a sea-island structure comprising a continuous phaseand a dispersed phase and also, an interfacial phase is the phasestructure which exists in the whole periphery of said dispersed phase.

The seventh aspect of the present invention according to any of thefirst point to the fifth point of the present invention relates to thethermosetting composition comprising wherein the average particle sizeof the dispersed phase observed by transmission electron microscope is20 μm or less.

The eighth aspect of the present invention according to any of the firstpoint to the fifth point of the present invention relates to thethermosetting composition comprising wherein the “thermosetting resin”(A) is epoxy resin or phenolic resin.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic illustration of a typical phase structure.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in detail as follows. Thethermosetting resin according to the present invention is defined to thematerial which is initially normal liquid low molecular weight compound(sometimes which can be called as prepolymer) and which has a propertythat generates propagation of polymerization of prepolymer andstructuralization of three dimensional network by bringing aboutchemical change on account of application of heat, catalyst orultraviolet ray and the like. Accordingly the heating is not alwaysrequired. To put concretely, typical examples are listed as phenolicresin, urea resin, melamine resin, epoxy resin, urethane resin, siliconeresin, alkyd resin, allyl resin, unsaturated polyester resin, diallylphthalate resin, furan resin, polyimide and the like.

Phenolic resin in the thermosetting resin according to the presentinvention is not limited specifically and is on the market, and novolaktype phenolic resin, which is given as an example, is obtained by themethod where phenol and formalin (formaldehyde aqueous solution) orformaldehyde are fed into a reaction vessel in the mole ratio of phenoland formaldehyde so as to be 0.5 to 1.0, and then, heated after additionof catalysts such as oxalic acid, hydrochloric acid, sulfuric acid, ortoluene sulfonic acid and the like, and after reflux reaction isconducted for a certain period of time, in order to remove separatedwater, vacuum dehydration or leaving-rest dehydration is conducted, andthen remained water and unreacted phenol are removed. Also, with respectto resol type phenolic resin, the above mentioned method can be used aswell by controlling the thermal history at dynamic heat treatmentaccurately. These resins or co-condensation phenolic resin obtained byuse of multiple raw materials are applied independently or by combiningtwo kinds or more.

As for epoxy resin of the thermosetting resin according to the presentinvention, properties, epoxy equivalent value, molecular weight,molecular structure and the like are not limited, and chemical compoundswhich have two oxirane-rings or more in one molecule can be applied, andpublicly known various types of epoxy resin can be used.

For example, glycidyl ether type epoxy resin such as bisphenol A,bisphenol F, bisphenol A bromide, or novolak glycidyl ether and thelike; glycidyl ester type epoxy resin such as hexahydrophthalic acidglycidyl ester and dimmer-acid glycidyl ester and the like; glycidylamine type epoxy resin such as triglycidyl isocyanurate or tetraglycidylphenyl methane and the like; linear fatty acid epoxy resin such as epoxypolybutadiene or epoxidized soybean oil and the like; and moreover,alicyclic epoxy resin such as 3,4-epoxy-6- methylcyclohexyl methylcarboxylate, or 3,4-epoxy cyclohexylmethyl carboxylate and the like;,can be listed and they can be applied with one kind or two kinds ormore.

Epoxy resin which exhibits liquid in room temperature is listed asrecommendable, for example, glycidyl ether type epoxy resin which isproduced under alkaline reaction condition between epichlorohydrin andaromatic chemical compound having one hydroxyl group or more is listedand concretely bisphenol A epoxy resin, or trade name of Epikote #828(Manufactured by Japan Epoxy Resin, Co., Ltd.) is listed.

The “reactive mono-olefin liquid polymer” according to the presentinvention is the polymer that various reactive functional groups areintroduced to mono-olefin polymer.

To be more precise, three kinds of liquid polymers are defined as,

(a) a liquid mono-olefin polymer having as least one epoxygroup(hereinafter referred to as “epoxy group containing mono-olefinliquid polymer ”), which epoxy group is introduced,

(b) a liquid mono-olefin polymer having at least one aldehydegroup(hereinafter referred to as “aldehyde group containing mono-olefinliquid polymer”), which aldehyde group is introduced,

(c) a liquid mono-olefin polymer having at least one ketonegroup(hereinafter referred to as “ketone group containing liquidmono-olefin polymer”),which ketone group is introduced.

The “reactive mono-olefin liquid polymer” according to the presentinvention can be easily produced by publicly known methods whichcarbon-carbon unsaturated bond in liquid polybutene is converted toaldehyde group and the like by means of publicly known techniques.

Hereinafter, as for the production of the “reactive mono-olefin liquidpolymer”, the recommendable production method of the “aldehyde groupcontaining mono-olefin liquid polymer” is given as the example.

To begin with, polybutene containing a large quantity of terminalvinylidene structure is produced in accordance with JP10-306128 A.According to said method, by the use of olefin raw materials which areconstituted by isobutene independently or isobutene and in some casesbutane-1, butane-2, they are made to polymerize by trifluoric boronbased catalyst, then since n-butene practically does not copolymerizewith isobutene, liquid polybutene which contains 60 mole percent or moreof terminal vinylidene structure, and also which has the Formula(1)structure with 80% or more of the repeating unit in the main chain, canbe easily obtained.

Then, epoxidized compound is obtained by conducting epoxidized reactionto said terminal position of carbon-carbon unsaturated bond withperoxide compound and the like (U.S. Pat. No. 3,382,255). Saidepoxidized product is epoxy group containing liquid polybutene(hereinafter referred to as “epoxy group containing mono-olefin liquidpolymer”) which epoxy structure is only formed virtually on the terminalcarbon.

Then, the “aldehyde group containing mono-olefin liquid polymer” isobtained by conducting isomerization reaction to the “epoxy groupcontaining mono-olefin liquid polymer”, which is publicly known anddescribed in, for example, JP 2908557 B, JP 3-503783 A.

The “reactive liquid polybutene” which is obtained by the abovementioned production method can be used in any form such as extremelypure product by isolation, a mixture of containing unreacted polybutenegroup without any change, or a mixture by further addition of liquidpolybutene.

The production method of the “aldehyde group containing liquidpolybutene” is recommendable from the point that unreacted product ineach process can be used directly, where polymerization reaction isconducted by using C4 olefin as raw material and polybutene, whichcontains terminal vinylidene structure having more than predeterminedmole percent, is made to produce “epoxy group containing liquidpolybutene” as chemical intermediate.

The “reactive mono-olefin liquid polymer” according to the presentinvention is preferable to have the number-average molecular weight inthe range of 300 to 6,000. In case of 6,000 or more, the effect ofimpact resistance and the like increases, but processability can be theproblem caused by the increase of viscosity. In case of 300 or less, asthe “epoxy group containing liquid polybutene” shown in EP045749A, sincemono-olefin polymer chain which is bonded to the “reactive mono-olefinliquid polymer” forms short length, the improvement effect of impactresistance and the like by solubilization into epoxy resin and the likebecomes dominant so that thermal resistance represented by HDT becomesdeteriorated.

A primary factor that the thermosetting resin composition according tothe present invention shows excellent in thermal resistance representedby HDP, impact resistance, and thermal crack resistance, is not clearlyexplained, and the inventors consider that the primary factor is causedby the affinity between the “reactive mono-olefin liquid polymer” andthe thermosetting resin, and peculiar phase structure observed bytransmission electron microscope. In FIG. 1 the brief figure of thetypical phase structure is shown.

When a curing reaction of common liquid polybutene is conducted bymixing with thermosetting resin, curing agent and the like, a sea-islandstructure (hereinafter referred to as “phase structure A”), which ismade by a continuous phase consisting primarily of cured product(hereinafter referred to as “cured product”) of thermosettingresin(including curing agent if necessary) and a dispersed phaseconsisting primarily of liquid polybutene, is formed, but thethermosetting resin according to the present invention forms the phasestructure which exists interfacial phase in the whole periphery of saiddispersed phase (hereinafter referred to as “phase structure B”). Also,the average particle size becomes the microscopic. Also, the thicknessof interfacial phase shows large size as the ratio of the “aldehydegroup containing liquid polybutene” in the “reactive mono-olefin liquidpolymer” is in larger quantity. This is considered that it is dependenton the reactivity difference between the “aldehyde group containingliquid polybutene” or other “reactive mono-olefin liquid polymer”, andthermosetting resin, curing agent, curing promoter and the like.Generally, in case of making the maximum thickness of interfacial phase,a whole quantity of the “reactive mono-olefin liquid polymer” needs onlyto be made as the “aldehyde group containing liquid polybutene”, whilein case of decreasing the thickness of the interfacial phase, the ratioof other “reactive mono-olefin liquid polymer” is made to increase.However, both “phase structure A” and “phase structure B” are notdisclosed in EP045749A.

Here, in both phases, as the average particle size of the dispersedphase observed by transmission electron microscope is smaller, theimpact resistance becomes excellent. Generally, the excellent propertiesexhibit in the range of 0.5 μm to 20 μm. According to the presentinvention, the adjustment of the average particle size can be conductedby the additive level of the organometallic compound and/or the metalester compound.

To be more precise, the “phase structure A” is the phase structure wherein the continuous phase which consists primarily of the cured productwhich shows high elasticity and brittle material, the dispersed phase ofμm unit size which consists primarily of component related to the“reactive mono-olefin liquid polymer” which has low elasticity and toughmaterial, exists. In the “Phase structure A”, when deformation by stressgenerates, by the difference of poisson's ratio between a component ofcontinuous phase and a component of dispersed phase, the force toseparate interface generates and separation occurs. Especially, as forthe “phase structure A” according to the present invention, the affinityof the continuous phase and the dispersed phase increases by theresemblance of chemical structure, so that energy consumed by saidseparation is large quantity. Stress (strain) is consumed (released) byseparation of said interface, crack and the like which is the cause offatal fracture of the material to the continuous phase in epoxy resindoes not generate and impact resistance and thermal crack properties areimproved.

Also, the “phase structure B” is the phase structure where in thecontinuous phase which consists primarily of the cured product whichshows high elasticity and brittle material, the dispersed phase of μmunit size which consists primarily of component related to the “reactivemono-olefin liquid polymer” which has low elasticity and tough materialexists, and moreover, it is the phase structure which exists interfacialphase of μm unit size having the main component of polymers asthermosetting resin, curing agent, and “reactive mono-olefin liquidpolymer” which have low elasticity and brittle material in the wholeperiphery. Said structure is the structure, which is confirmed in thephase structure of impact resistant polypropylene resin (block typepolypropylene), and which is called as multi-phase structure.

To be more precise, as for impact resistant polypropylene resin, thedispersed phase which is formed by polyethylene exists in the continuousphase which is formed by polypropylene, and the interfacial phase whichis formed by ethylene-propylene copolymer rubber in the periphery ofpolyethylene dispersed phase, exists. In the “phase structure B”, when adeformation generates by a stress, in addition to the consumption(release) of the stress(strain) generated in the “phase structure A”, atinterfacial phase as well, by boundary separation, similarly thestress(strain) is consumed(released) so that the boundary separationenergy generated per unit volume is larger compared with “phasestructure A”. Accordingly, crack or the like which is the cause of fatalfracture of the material in the cured product continuous phase does notoccur and impact resistance and thermal crack properties are improvedmore effectively.

In order to develop phase structure according to the present invention,the organometallic compound and/or the metal ester compound of thepresent invention is used.

The organometallic compound means that organic portion represented byalkyl group and metal are formed in chemical-bonding while metal estercompound means that fatty acid and metal are bonded in the state ofester-bonding. In case when used in the present invention, the twocharacteristics that can be expected are listed as follows.

(1) Dispersion effect of the “reactive mono-olefin liquid polymer” inthe thermosetting resin continuous phase

(2) Coordination effect to oxygen atom in the “reactive mono-olefinliquid polymer”

To begin with, dispersion effect of the “reactive mono-olefin liquidpolymer” is explained. In order to control the dispersion particle sizeof the above mentioned “phase structure A” and/or “phase structure B”,in the thermosetting resin composition, the dispersion state of the“reactive mono-olefin liquid polymer” is necessary to control so thatthe compatibility between the thermosetting resin and the “reactivemono-olefin liquid polymer” grows important. Organic part of theorganometal according to the present invention can provide interfacialactive role to the thermosetting resin and the “reactive mono-olefinliquid polymer”, and a certain level of the dispersion state can beobtained.

For the preferable structure as the organic part, paraffin having chainbranch or paraffinic fatty acid having chain branch can be listed. To bemore precise, the paraffinic chain branch having chain branch ispreferable to improve diffusion properties in the “reactive mono-olefinliquid polymer” system. Also, alicyclic carboxylic acid structure asnaphthenic acid compound is recommendable from the above mentionedreason. Naphthenic acid is defined as the naphthenic acid which issaturated carboxylic acid group having naphtheic nuclei, and which isthe main component of petroleum acid, and the structure of thenaphthenic acid is shown as polymethylene carboxylic acid correspondingto general formula C_(n)H_(2n)-₂O₂ (mono-cyclic), C_(n)H_(2n)-₄O₂(bi-cyclic), or moreover, C_(n)H_(2n)-₆O₂ (tri-cyclic) and the like.

Then, in case of selecting a substance which can make coordinate-bondingto metal part in organometal with oxygen atom in the “reactivemono-olefin liquid polymer”, the “phase structure B” formation ispossible to be accelerated. For a kind of metal, metals havingcoordination bond capability such as cobalt, zinc, tin, copper and thelike are recommendable. Here, after having coordination bonding, bycatalytic function of said metal compound, the followings and the likeare also possible to confirm, where:

1. Epoxy group becomes aldehyde group or ketone group by convertingfunction group in the “reactive mono-olefin liquid polymer”, then

2. As a result that the reaction between the “reactive mono-olefinliquid polymer” which is formed to aldehyde group or ketone group andthermosetting resin and the like makes progress, a fact that the “phasestructure B” is formed and the like ,but details are unknown.

The recommendable concrete examples of the above describedorganometallic compound and/or metallic ester compound are listed asbutyl tin, octyl zinc and the like for the organometallic compound, and(di)tin octylate, (di)zinc octylate, tin naphthenate, zinc stearate andthe like for the metallic ester compound, but these are not limited.Also, the organometallic compound according to the present invention canbe used independently or mixture of two kinds or more.

In producing the thermosetting resin according to the present invention,for the total of the thermosetting resin and the curing agent of 100parts by weight, the “reactive mono-olefin liquid polymer” of 1 to 200parts by weight, preferably of 5 to 100 parts by weight can be added.The organometallic compound and/or the metallic ester compound of 10 to1,000 ppm parts by weight are added. As the larger additive level of theorganometallic compound and/or metallic ester compound, the particlesize of the dispersed phase in the sea-island phase becomes small, andalso becomes uniform

As the curing agent which is added at need according to the presentinvention, any kind which reacts with the above mentioned thermosettingresin or the “reactive mono-olefin liquid polymer” and which ispracticable to cure, can be applied, and for epoxy resin taking as anexample, poly-addition type curing agent such as aliphatic polyamine,alicyclic polyamine, aromatic polyamine, anhydride based (methyl hexahydrophthal anhydride, phthalic anhydride derivatives and the like);,catalytic type curing agent such as aromatic tertiary amine, imidazolecompound, Lewis acid complex and the like; can be listed. Also, thecuring agents listed above can be used independently or blendingtogether in the range which does not hinder curing.

The component besides the thermosetting resin, the curing agent, and the“reactive mono-olefin liquid polymer” used for the present invention iscuring promoter if taking epoxy resin as the example in thethermosetting resin. As concrete examples, amine based compound and itssalt compound such as benzyl dimethyl amine(BDMA),1-benzyl-2-phenylimidazole, 2-heptadecylimidazole;2-phenyl-4,5-dihydroxyimidazole,2-phenyl4-methyl-5-hydroxymethylimidazole,2,4-diamino-6-[2-methylimidazolyl-1)]-ethyl-s-triazine,1-cyanoethyl-2-undecylicimidazole, 2-ethyl-4-methylimidazle, 1,8-diazabicyclo [5,4,0]undecene-7 and the like; phosphine based and its saltcompound such as triphenylphosphine,tres-(2,6-dimerthoxyphenyl)phosphine and the like;and ornanometallicsalt;, can be listed. As for producing the thermosetting resin compoundaccording to the present invention, if epoxy resin is taken as anexample, for 100 parts by weight of the total with the curing agent ofthe thermosetting resin, the curing promoter can be added to 0 to 20parts by weight.

In case that the composition according to the present invention isapplied to the various applications, as components besides the abovementioned, the publicly known liquid rubber such as liquid reactiverubber, liquid a-olefin polymer and the like; impact resistanceimprovement such as elastomer, core-shell structure elastomer; fillerssuch as flame retardant, coupling agent, anti-foam agent, pigment, dye,antioxidant, weathering agent, slipping agent, mold release agent andthe like;, can be added and blended appropriately within the limitswhich do not impair the effect of the present invention. Moreover,liquid polybutene group having other basic structure and/or chemicallymodified structure can be applied.

Moreover, as for fillers, molten silica, ground silica, talc, calciumcarbonate, aluminum hydroxide and the like can be listed and in case ofmaking application to the encapsulation of semi-conductors in the resentyears, molten silica having 20 μm or less of average particle size isrecommendable and they can be used independently or combination of anyquantity by mixing two kinds or more.

EXAMPLES

The present invention is described in detail according to Examples asfollows.

Reference Production Examples Production of “Reactive Mono-Olefin LiquidPolymer”

The liquid polybutene reference numerals 1 to 6 shown in Table 1 areused as raw materials and “reactive mono-olefin liquid polymer” 1ab to6ab are produced. The attached letter “a” corresponds to “epoxy groupcontaining mono-olefin liquid polymer” and the attached letter “b”corresponds to “aldehyde group containing mono-olefin liquid polymer”,which are their raw materials. Reference numerals 1 and 2 amongreference numerals 1 to 6, are LV50 and HV-100 respectively, which aremanufactured by Nippon Petrochemicals Co., Ltd., which are obtained frommarket, and which have rich vinylidene terminated structure (commonlycalled by “highly reactive polybutene”) obtained by Reference ProductionExamples 3 to 6 or by the production method JP10-306128 A which isdisclosed by the inventors.

The “epoxy group containing mono-olefin liquid polymer”(ReferenceProduction Examples 1a to 6a) is produced by reacting the abovementioned liquid polybutene reference numerals 1 to 6 with peracidreferring to the above mentioned U.S. Pat. No. 3,822,55, and the“aldehyde group containing mono-olefin liquid polymer” (RerenceProduction Examples 1b to 6b) is produced by isomerization of the abovementioned “epoxy group containing mono-olefin liquid polymer” (ReferenceProduction Examples 1a to 6a) as raw material which is made to act 98percent by weight sulfuric acid, referring to the method of the abovementioned JP2908557 B.

Each chemical modification is conducted until terminal vinylidenestructure and epoxy group structure in the raw materials are notvirtually detected. TABLE 1 Mono-olefin (Corresponding) (Corresponding)Liquid Polymer Epoxy Group Aldehyde Group Number- containing containingaverage Mono-olefin Mono-olefin Molecular Liquid Polymer Liquid Polymername Content Weight (*1) name name 1 LV-50 430 1a 1b 2 LV-100 980 2a 2b3 Highly 370 3a 3b Reactive Polybutene 4 Highly 650 4a 4b ReactivePolybutene 5 Highly 1300 5a 5b Reactive Polybutene 6 Highly 2300 6a 6bReactive Polybutene(*1): Shown number-average molecular weight (polystyrene convertedvalue) by GPC measurement

Examples 1 to 6, Comparative Examples 1 to 3 Examples of Epoxy ResinCuring Reaction and Evaluation of Physical Properties to FinalComposition

As experimental apparatus, variable type agitator, reaction temperatureindicator, and flask which is equipped with reaction dropping gate, areprovided in the constant temperature controllable heating medium bath.

The curing reaction is fixed as selecting curing agent/epoxy resincomponent with MH700/Epikote #828, so as to be functional groupequivalent ratio 0.9 in all the conditions. To the curing agent/epoxyresin component, each kind of reactive mono-olefin liquid polymer andorganometallic compound and/or metallic ester compound are added so asto be component ratio shown in Table 2, and then are agitated forblending.

After confirming that the component becomes uniform, three steps ofthermal history as (1) 100° C.×2 hours, (2) 120° C.×2 hours and (3) 140°C. ×2 hours are given, and each epoxy resin cured products are obtained.

Also, the component of abbreviated expressions used in Examples will bedescribed as follows.

Epikote #828(Manufactured by Japan Epoxy Resins Co., Ltd.):

Epikote #828 is the epoxy resin which consists primarily of bisphenol Adiglycidyl ether. The equivalent value of functional group (epoxy group)is approximately 190 g/eq.

MH-700(Manufactured by New Japan Chemical Co., Ltd.):

MH-700 anhydride based curing agent consists primarily of methylhexahydro phthalic anhydride. The equivalent value of functionalgroup(anhydride group) is approximately 168 g/eq.

BDMA (Reagent of Tokyo Kasei Kogyo Co., Ltd.): benzyl amine.

(di) tin octilate(Reagent of Kishida Chemical Co., Ltd):

Another name is tin 2-ethyl hexanate and tin content of approximately28% product is used.

The evaluations of physical properties of epoxy resin components areconducted for 5 items which are flexibility, moisture resistance, crackresistance, chemical resistance and thermal resistance. For theevaluations of physical properties, about components obtained from eachExample and each Comparative Example, test specimens applicable to eachmeasurement are taken.

Evaluation Methods of Physical Properties

Each evaluation method of physical properties will be described.

Moisture resistance: Cured product specimen is kept in boilinq water for10 hours; and moisture resistance of cured product is evaluated by theweight difference of before and after the exposure. Test is conductedfor two times and the average value is obtained. Crack resistance:Japanese Industrial Standards (JIS)-C-2105(Electrical Insulating Non-solvent Resin Test Method) is applied and 5 pieces of cured product testspecimens which metal washers having different heat conductivity areencapsulated, are prepared, and crack is observed while each testspecimen is cooled from 150° C. to 0° C., and the average crack numberis calculated. Thermal resistance: Heat distortion test (HDT) ismeasured based on Japanese Industrial Standards (JIS)-K-6901, and thethermal resistance of the cured product is evaluated from the measuredvalue. The measurement is conducted for 5 times and the average value isobtained.

Phase structure observation: Phase structure of Examples and ComparativeExamples are observed by the use of transmission electron microscope(TEM)“Apparatus name JEM-1010” manufactured by JEOL. Ltd. Acceleratingvoltage is 100 kV, and ruthenium oxide is used for dyeing. Accordingly,dying phase is concluded that the phase consists primarily of the“reactive mono-olefin liquid polymer”.

In Table 2, formulation condition of serial epoxy resin composition andthe evaluation results of physical properties are shown. TABLE 2Comparative Examples Examples Formulation 1 2 3 4 5 6 1 2 3 Reactive 1a10 10 Mono-olefin Liquid 1b 10 Polymer(*1) 3a 10 10 3b 10 10 5b 10O.C.M.C.(*4) Octylate 350 165 165 350 165 350 0 0 0 Tin(*2) CuringPromoter BDMA 1 Physical Properties-Evaluation Moisture ResistanceBoiling Water 1.1 0.9 1.0 0.8 1.0 1.0 1.2 1.1 1.0 Resistance CrackResistance Average 0 0 0 0 0 0 2 1 7 Crack Number Thermal Resistance HDT(° C.) 120 128 122 131 128 134 118 122 133 Phase Structure B B B B B BAverage Particle μm <20 <15 <15 <10 <15 <10 >35 >50 SizeDistribution(*3)(*1)Formulation is shown as weight percent in cured resin.(*2)Formulation is shown as weight ppm in cured resin.(*3)As for 50 dispersed phase in the printed image used for <phasestructure observation>, the particle size is measured and average iscalculated.(*4)Organometallic Compound and/or Metallic Ester Compound

INDUSTRIAL APPLICABILITY

By a thermosetting resin composition which is formed by reaction ofcomposition by a formulation of a thermosetting resin, a curing agent, acuring promoter, and a “reactive mono-olefin liquid polymer” and anorganometallic compound according to the present invention, the existingproblem on physical properties is concluded to be solved. The reason whythe problem can be solved as such is that, as the main phase structure,a sea-island structure is made to develop a continuous phase whichconsists primarily of cured product of the thermosetting resin(including the curing agent) and a dispersed phase which consistsprimarily of “reactive mono-olefin liquid polymer”, and moreover, aninterfacial phase is made so as to have at least one phase in the wholeperiphery of said dispersed phase.

1. A thermosetting composition comprising (A) a thermosetting resin, (B)any one or more liquid mono-olefin polymers (a) to (c) wherein: (a) theliquid mono-olefin polymer has at least one epoxy group, (b) the liquidmono-olefin polymer has at least one aldehyde group, (c) the liquidmono-olefin polymer has at least one ketone group, and (C) anorganometallic compound and/or a metal ester compound.
 2. Thethermosetting composition according to claim 1 wherein the mono-olefinliquid polymer (a) has the epoxy group formed on a terminal carbon,and/or the mono-olefin liquid polymer of (b) has the aldehyde groupformed on a terminal carbon.
 3. The thermosetting composition accordingto claim 1 wherein 80% of the mono-olefin liquid polymer is a repeatingchain represented by the structure


4. The thermosetting composition according to claim 1 wherein anumber-average molecular weight of the mono-olefin liquid polymer is inthe range of 300 to 6,000.
 5. The thermosetting composition according toclaim 1 wherein the organometallic compound and/or the metal estercompound is any of (d) to (f); wherein (d) a metal part is any ofcobalt, tin, zinc, copper; (e) an organic structure part is a paraffinor a fatty acid having chain branch of 10 or fewer carbons in a mainchain, (f) an organic structure part is a naphthenic acid base fattyacid.
 6. The thermosetting composition according to claim 1 wherein amain phase structure of said resin is a sea-island structure comprisinga continuous phase and a dispersed phase and wherein a surface phase isa phase structure which exists in a whole periphery of said dispersedphase.
 7. The thermosetting composition according to claim 1 wherein anaverage particle size of a dispersed phase of said resin as observed bya transmission electron microscope is 20 μm or less.
 8. Thethermosetting composition according to claim 1 wherein the thermosettingresin (A) is an epoxy resin or a phenolic resin.
 9. The thermosettingcomposition according to claim 2 wherein: 80% of the mono-olefin liquidpolymer is a repeating chain represented by the structure

a number-average molecular weight of the mono-olefin liquid polymer isin the range of 300 to 6,000; the organometallic compound and/or themetal ester compound is any of (d) to (f); wherein (d) a metal part isany of cobalt, tin, zinc, copper; (e) an organic structure part is aparaffin or a fatty acid having chain branch of 10 or fewer carbons in amain chain; (f) an organic structure part is a naphthenic acid basefatty acid.
 10. The thermosetting composition according to claim 9wherein a main phase structure of said resin is a sea-island structurecomprising a continuous phase and a dispersed phase and wherein asurface phase is a phase structure which exists in a whole periphery ofsaid dispersed phase.
 11. The thermosetting composition according toclaim 9 wherein an average particle size of a dispersed phase of saidresin as observed by a transmission electron microscope is 20 μm orless.
 12. The thermosetting composition according to claim 9 wherein thethermosetting resin (A) is an epoxy resin or a phenolic resin.